Fuel injectors with misalignment compensation

Abstract

A fuel injector assembly including a member and a seat. The member has a first center along a longitudinal axis. The member has a curved surface and a flat surface. The curved surface has a radius of curvature greater than a width of the member. The flat surface is axially opposed to the curved surface. The seat has a second center disposed on the longitudinal axis. The seat is positioned distal from the flat surface defining a flow path in an open position of the fuel injector assembly and is in confronting relation to the flat surface such that the second center is concentric to the first center forming a sealing interface in a closed position of the fuel injector assembly.

What is claimed is: 
     
       1. A fuel injector assembly comprising:
 a member having a first center along a longitudinal axis, the member comprising:
 a curved surface having a radius of curvature, the radius of curvature of the curved surface being greater than a width of the member, and 
 a flat surface axially opposed to the curved surface; and 
 
 a seat having a second center disposed on the longitudinal axis, the seat being positioned distal from the flat surface defining a flow path in an open position of the fuel injector assembly, and in confronting relation to the flat surface such that the second center is concentric to the first center forming a sealing interface in a closed position of the fuel injector assembly. 
 
     
     
       2. The fuel injector assembly of  claim 1 , further comprising a member guide configured to limit translation of the member in a radial direction. 
     
     
       3. The fuel injector assembly of  claim 1 , further comprising:
 a stator defining a bore along the longitudinal axis; and 
 an armature assembly configured to translate along the longitudinal axis, the armature assembly comprising an armature plunger positioned in the bore and a cap coupled to the armature plunger. 
 
     
     
       4. The fuel injector assembly of  claim 3 , wherein the member is in confronting relation to the cap, and wherein the cap defines a first profile and the member defines a second profile, the first profile configured to receive the second profile and the second profile configured to receive the first profile when the first profile receives the second profile. 
     
     
       5. The fuel injector assembly of  claim 4 , wherein the first profile comprises a convex profile and the second profile comprises a concave profile. 
     
     
       6. The fuel injector assembly of  claim 4 , wherein the first profile comprises a concave profile and the second profile comprises a convex profile. 
     
     
       7. The fuel injector assembly of  claim 4 , wherein the first profile is configured to allow the cap to roll off of the second profile to compensate for translation of the member at an angle when the armature assembly longitudinally translates towards the seat. 
     
     
       8. The fuel injector assembly of  claim 3 , wherein the armature assembly further comprises:
 an armature coupled to the armature plunger; and 
 a biasing member positioned radially relative to the armature, the biasing member configured to compensate for overtravel of the armature when the armature assembly longitudinally translates towards the seat. 
 
     
     
       9. The fuel injector assembly of  claim 3 , further comprising a raised interface defined by a first surface of the member in confronting relationship with a first surface of the cap, the first surface of the cap receiving the first surface of the member and the first surface of the member receiving the first surface of the cap in the closed position,
 wherein the armature plunger has a third center, and wherein the raised interface seals a pressurized fuel from a low-pressure drain circuit in the closed position when the second center and the third center are nonconcentric. 
 
     
     
       10. The fuel injector assembly of  claim 9 , wherein the armature assembly further comprises an armature positioned around an end of the armature plunger, wherein a biasing force is applied upon the armature as the fuel injector assembly transitions to the closed position, and wherein the first center and the third center become concentric within an overtravel gap when as the fuel injector assembly transitions to the closed position, the overtravel gap being an axial distance between an end surface of the armature and a second surface of the cap, the second surface of the cap being axially opposed to the first surface of the cap. 
     
     
       11. The fuel injector assembly of  claim 1 , wherein the seat comprises:
 an inlet configured to receive fuel in the open position; and 
 a raised perimeter around the inlet. 
 
     
     
       12. The fuel injector assembly of  claim 11 , wherein the seat further comprises a plurality of raised features positioned radially away from the raised perimeter, the plurality of raised features are configured to interface with the member to compensate for translation of the member at an angle, each of the plurality of raised features comprising an angled surface relative to the longitudinal axis and a plurality of raised sections. 
     
     
       13. The fuel injector assembly of  claim 12 , wherein the plurality of raised sections comprises three raised sections. 
     
     
       14. The fuel injector assembly of  claim 12 , wherein the raised perimeter defines a first height and the plurality of raised features defines a second height, the first height exceeding the second height. 
     
     
       15. The fuel injector assembly of  claim 12 , wherein the raised perimeter defines a first height and the plurality of raised features defines a second height, the second height exceeding the first height.